Refrigerator car



P. TALMEY REFRIGERATOR CAR INVENTOR. PazaZ iZzZme Patented June 23, 1953UNITED STATES PATEN OFFICE REFRIGERATOR CAR Paul Talmey, Chicago, Ill.,assignor to General American Transportation Corporation, Chicago, 111.,a corporation; of New York Application November 5, 1947, Serial No.784,203

8 Claims. (01. 105-409) This invention relates to refrigerator cars andthe like, and has for its principal object the provision of a new andimproved device of this kind.

It is a main object of the invention to provide new and improvedinsulation for refrigerator cars and the like.

Another object of the invention is to provide within the car acontinuous insulation of low thermal conductivity, uninterrupted bymaterials of higher thermal conductivity.

Another object of the invention is to provide an insulation sandwich oflow thermal conductivity and having suflicient strength to enable it tosupport the load within the car.

Another object of the invention is to provide 2 trucks and the like,usually consist of an outer shell frequently composed of metal andsurrounding an inner shell that is spaced inwardly therefrom with theintervening space occupied by an insulation for a refrigerator car andthe like that is both moistureand vermin-proof.

Another object of the invention is to provide for insulatingrefrigerator cars and the like at low cost both as to initial cost andmaintenance.

Another object of the invention is to eliminate the framing membersformerly used to affix thermal insulation to the Walls of a refrigeratorcar and the like.

Further objects of the invention not specificalof the car takensubstantially along the longituclinal median line thereof;

Fig. 3 is a transverse cross sectional view taken substantially alongthe line 3-3 of Fig. 1, looking in the direction of the arrows;

Fig. 4 is a fragmentary cross sectional view drawn to an enlarged scaleand showing one method of attaching the insulation to the car shell;

Fig. 5 is a fragmentary cross sectional view taken along thelongitudinal median line of the car and showing particularly thesecuring of the insulation ceiling to the roof of the car;

} Fig. 6 is a view similar to Fig. 5, .takensub stantially along theline 6-5-6 of Fig. 1, looking in the direction of the arrows; and j IFig. Tie a vertical cross sectional view'through the door of the cartaken substantially along the line 1-1 of Fig. 2 looking in thedirection of the arrows.

Refrigerated freight cars,refrigerated trailer thermal insulation eitherin the form of a blanket, molded slabs or pellets. Generally the innershell of the structure is composed of wood and is supported in spaced.relation with respect to the outer shell by numerous brackets .and/or'framing members extending therebetween, which members invariably have ahigher thermal conductivity than the insulation, with the result thatheat losses are increased adjacent each of these members. When theblanket or other nonrigid type of insulation is used, it is necessary tofasten such insulation to the walls of the car with wooden framingmembers, which furnish additional conductive paths between the inner Iand outer shells.

In the prior art of which I am aware, numerous attemptsvhave been madeto remedy this condition, the most common being forming theinsulationinto separate layers and providing separate members; the oneon-the outer shell and the other on the inner shell, which members arestaggered and connected together by material of relatively low thermalconductivity. While this arrangement materially increases-the length ofthe path over which the heat must travel in entering or escaping fromthe car and thereby lessens the losses encountered when solid directmembers are employed, the results are still far from ideal because theinner and'outer shells.

are connectedtogether at points having thermal conductivity that ishigher than the main insulation. The present invention seeks to overcomethis difiiculty.v

In the floors of prior art cars of which I am aware, it has beengenerally necessary to provide additional support since the insulatingmaterials 1 commonly used herebefore are so highly compressible as tomake necessary the provision of load supporting brackets or joists forsupporting the floor of the innershell above the floor of the outershell of the vehicle. In instances where supporting brackets have beenomitted, the weight of the load has depressed the floor and therebycompressed the. insulation to: such an extent that its thermalconductivity has been materially increased.

a The present invention provides for insulating the outer shell ofstructures such as refrigerator cars by means of a sandwich ofinsulating material, which sandwich consists of a central body of, lowthermal conductivity and of sufiicient strength in compression to enableit to support the load without the use of additional supporting means.Fixed to the inner and outer surfaces of this central body of insulationis a sheet of rigid material. These sandwiches cover the entire innersurface of the outer shell, that is the door, floor, roof, side wallsand end walls thereof. The infier ones 'of the rigid sheets that arefixed onto the insulating central bodies provide a smooth inner shellfor the vehicle, which inner shell is separated from the outer shell ofthe vehicle by a continuous band of insulation that is uninterrupted bypaths of material of thermal conductivity higher than that oftheinsulation.-

In one embodiment of the invehtion,the cen-' tral body of insulatingmaterial consists of foamed plastic, such as polystyrene;,expa nded witha gasifying agent so that the resulting structure contains a myriadoftiny closed air cells. It is understood, of course, that any materialhaving a comparatively rigid structure, high compressive strength, and arelatively high tensile strength combined with a low thermalconductivity constant, known as the K factor, could be employed in sucha sandwich without departing from the spirit of the invention. Severalother such materials are now available on the market such as foamed hardrubber and foamed urea formaldehyde for example.

The rigid sheets applied to the opposite faces of this central body offoamed polystyrene are, in the preferred embodiment; composed of plywoodalthough one or both sheets could be of steel or plastic or any materialthat can be emciently utilized for fastening members. These rigid sheetsare fixed to the central body suitably by cement and the individuallaminae of the sheets are fixed together by suitable cement. whichcements are moistureproof so as to render the sandwich so formedrelatively unaffected by moisture. The sandwiches used in the floor ofthe car, contain on their upper surfaces a thicker rigid sheet alsocomposed of plywoods which serves as an inner floor for the car. Aparticular advantage resulting from the use of these sandwiches, affixedto the external shell of the car in a manner to be subsequentlydescribed, is the elimination of the use of framing members needed tohold the insulation in place against the walls of the car. These membersare the source of considerable heat loss no matter how low the thermalconductivity of the insulation. Cork and similar insulating materialsmight not require framing members but are impractical because of theirhigh cost and excessive weight. Such materials can, however, utilize theteachings of this invention for assembly and installation.

Many refrigerator car designs call for a smooth exterior surface in theouter shell of the car, with the result that vertical posts extend fromtop to bottom of, the car at frequent intervals on the inside surface ofthis outer shell. When such a car is insulated with sandwiches of thetype employed in the present invention, the outer rigid sheets of thesandwiches are disposed in line with the inner surfaces of the posts,with the result that there is an air space or spaces between theinsulation and shell of the car. Also the roofs of many cars areprovided with rafterlike members, called carlines, that dependdownwardly into the interior of the car, in which case the insulationceiling will be supported from these carlines with an air space above itand between it and the roof of the car. In other instances where theinner surfaces of the outer shell are smooth, the insulation sandwicheswill be placed directly thereagainst with no air spaces intervening.

Referring now to the drawings in more detail wherein a preferredembodiment of the invention is shown by way of example applied to atypical refrigerator car, it will be seen that the car comprises anunderframe 10 supported on suitable trucks, not shown, and supporting asub-floor l2 from the opposite edges of which side walls 13 and I4extend upwardly, and are connected together by roof members 15 and i6.The ends of the car are closed in by end walls ll all of which membersin the example shown are assumed to be metal.

As will be seen in Fig. 4, the side walls 13 and [4 are composed of aplurality of individual sheets lapped together and riveted to posts 20that extend from top to bottom of the car. As will be seen best in Figs.2 and 5, the roof members l5 and [8 are supported by carlines II whichdepend therebelow. The particular details of the structure of the outershell of the vehicle are not of the essence of the present invention.

The outer shell so formed is insulated in the preferred embodiment ofthe invention by sandwiches 30 laid on the floor 12 of the car andextending laterally thereacross into substantial abutment with theinside surfaces of the outer side walls 13 and I4. The sandwichesconsist of a central body 3| composed of a rigid insulating materialhaving a low K factor. Foamed polystyrene, as commercially available,for example, has a K factor in the order of .27; that is to say, thethermal conductivity of the material permits a layer of material oneinch thick and one foot square to pass 27/100 B. t. u. per hour for eachdegree of temperature difference between the two surfaces of thematerial. The above given K factor is not substantially different frompresent available non-rigid insulation. Some of the advantages of thismaterial which should preferably be possessed by the material used inthe central body of such a sandwich, are high compressive strength,relatively high tensile strength, virtual resistance to insectinfestation, almost complete impermeability to moisture and a lowspecific density. Fixed to the upper and lower surfaces of this material3| are rigid sheets 32 and 33 which are of themselves preferablycomposed of material such as wood. As will be seen in Fig. 3, the upperrigid sheet 32 is substantially thicker than the lower sheet 33 and eachis composed of several laminations of wood.

Similarly the inner faces of the side walls of the outer wall areinsulated by sandwiches 40 which consist of a main central body 4! ofrigid insulating material of low thermal conductivity to the oppositefaces of which body rigid sheets 42 and 43 are attached. Sheets 42 and43 may likewise be plywood. The end walls of the shell likewise areinsulated by sandwiches 45 which consist of a central body 46 composedof similar insulating material, and to which facing members 41 and 48are attached. The roof is insulated by sandwiches 50 each comprising acentral body of similar insulation 5| with upper and lower facing 52 and53 respectively, which facings may also be plywood.

As will be seen in Figs. 2 and 3 in the end of the car, wherein isdisposed the ice bunkers 56 the near sandwich 51-15 somewhat thinnerthan the main floor in the car. The interior surface of the bunker islined by suitable material 58,

such as metal, to protect it from damage that might result by dropping.cakes of ice into the bunker. The floor of the bunker is equipped with apan 59 through which water dripping from the melting ice is collectedand drained out of the car through a suitable trap, not shown.

In order to facilitate handling, sandwiches are preferably made in aconvenient width, say four feet, and these sandwiches arestep-cut alongopposite edges to form a so-called ship-lap joint, which permitsbreaking up the seams between adjacent members, thereby decreasing heatlosses along those seams. As will be seen in Fig. 4, the centralinsulation 4| of the side wall panels is step-cut at 60 approximatelyalong the transverse median line of the sandwich and the inner facing 42is offset with respect to the outer facing 43 so as to form atypicalship-lap joint. The sandwiches used on the floor ends and roof ofthe car are similarly ship-lapped. If desired, a single sandwichextending from the center door to the end of the car may be substitutedfor the plurality of panels shown. As will be seen best in Fig. 2, thefloor sandwiches wherein the upper rigid sheets 32 are of appreciablethickness may also be ship-lapped in this sheet 32 if desired.

, tightened.

The individual sandwiches disposed on the floor of the car are securedthereto in a manner best seen in Fig. 3. The upper facing 32 contains aperforation ID that registers with a perforation H in the central bodyof insulation 3!. A bolt 72 is extended up through the sill of the carand through the lower facing 33. A nut 13 is threaded onto this bolt tobind the sandwich to the floor I2 of the car. Several such bolts will beused in each of the sandwiches on the door. After the nuts have beentightened down,

the perforation II in the central insulating body i is filled with aplug which may be of the same material as the body andis cemented intoplace so as to remain fixed. If desired, in lieu of said plug, theperforation can be filled by pressure injection of the same or otherinsulating material in plastic form so as to create a tighter bond onhardening and also serve the purpose of cementing the nut on the boltand prevent its working loose. In fact, any type of low K factormaterial can be utilized to plug and seal the perforation either as aformed plug forced and cemented into place, or otherwise forced intosaid opening. The perforation it in the upper facing 32 may be similarlyplugged and sealed so as to render the floor smooth and free fromperforations.

As will be seen in Fig. 4, in cases Where the side walls of the vehiclecontain vertically extending posts it, brackets 88 are attached to theseposts preferably by welding, and the edges of the central insulatingmaterial and outer facings of the sandwiches are cut away at 8| to fitover the post. The central body of insulating material is perforated asat 82 and the inner face ing 42 contains a perforation 83 through whichbolts 84 that extend through the brackets 80 and the outer facing 43 areaccessible. After the nuts on the bolt have been tightened perfora"tions 82 and 83 are blocked and sealed to render the side wallscontinuous and uninterrupted.

Roof members [5 and I6 of the outer wall are pitched to provide fordrainage and the carlines 25 are appreciably thicker at the center ofthe car than at the edges. Preferably the ceiling panels 56 are disposedhorizontally and equi-distant from the floor and are attached to thesecarlinesby brackets best seen. in Figs. 5 and 6.

Brackets extend substantially below the lowermost section of thecarlines 2!. As will beseen in Fig. 6, the outer edges of the carbrackets are attached to the carlines 2| above the lowermost portionstherefrom and extended laterally therefrom. Bolts 9| project throughthese brackets and the upper facings 53 of the ceiling sandwiches 59 tosupport the sandwiches thereagainst.

It will be noted that the side wall sandwiches rest upon the uppersurfaces of the floor sandwiches 3t and are step-cut along their upperedges to permit the ceiling sandwiches to extend beyond the inner facesof the side wall sandwiches and that the end wall sandwiches aresimilarly located. As a result of this construction, the juncture linebetween floor and side wall and side wall and roof are in effect shiplapped so that heat in passing through this joint must travel a paththat is substantially longer than the straight line distance between theinner and outer facings of the sandwiches.

As will be seen in Fig. 7, thedoors by which access to the car isobtained are framed with suitable members N13 with which the interiorfacings 42 are ship-lapped. The door itself consists of a suitable frameI III, generally rectangular and closed in by an insulation sandwichI02, which is'of the same general construction as the other sandwiches.The outer surface of the door may contain a metal facing I03 if desired.The door frames and bunker hatch frames, if used, constitute the onlyplaces in the entire car where there is a direct path between the innerand outer shells that is filled with a material other than the maininsulating material employed.

JIhecar insulated in the foregoing manner has been found to havesubstantially lower heat losses than have prior art refrigerator cars.The main insulation combines a low thermal conductivity with greatstrength in compression, and when coupled in a sandwich with plywood theproduct is a very satisfactory insulation for structures of this kind.When composed of such materials cemented together by suitablemoistureproof cement, the resulting structure is virtually impervious tomoisture and vermin. The insulation is not fragile and not subject topack ing by vibration or static loading of the car. Furthermore there isa considerable saving in weight, which is extremely important in thisfield.

While this type of insulation has been described as being used insandwich form, additional savings in construction costs and weight arepossible by omitting either one or both of the plywood sheets. That isto say, it is entirely feasible to apply the blocks of insulationdirectly to the shell of the car, having plywood facing only forthe'interior walls and ceiling of the car. With certain types of lading,even the interior of the car can be finished with the insulation itself.Foamed polystyrene, for instance,.

has sufficient structural strength to be bolted onto the shell of thecar and have the perforations filled and sealed as above-described.

While I have illustrated a refrigerator car sesame with the inventionapplied thereto, 1. have done so by way of example only, as. theinvention may be applied to any structure wherein heat, insulation isdesired and wherein the temperatures encountered are within the rangethat materials employed are capable of withstanding. I have illustrateda specific embodiment.- of the invention for the purpose of.illustration and there are many modifications and adaptations which canbe made by one skilled in the artv within the teachings of theinvention.

Having thus complied with the statutes, and shown and described apreferred embodiment of the invention, what I consider new and desire tohave protected by Letters Patent is pointed out. in. the. appended.claims.

What is claimed is:

l. The combination with a refrigerator car. having an outer shell.having internal posts and carlines, of a thermal insulation liningcomprising: sandwiches composed of a sheet of multicellular material ofhigh compressive strength, sheets of rigid fibrous material secured onthe opposite faces of said multi-cellular material, brackets on theposts and carlines of the shell of the car against which the outersheets of fibrous material are disposed. bolts extending through saidouter sheets and brackets to secure the sandwiches to the brackets, saidmulti-cellular sheets and inner fibrous sheets being perforated to giveaccess to the bolts, and plugs composed of the same materials as thesandwiches for plugging said perforations after the bolts have beentightened.

2. The combination with a refrigerator car having an outer shell havingposts and carlines, of a thermal insulation lining comprising:insulation sandwiches each comprising a central body of multi-cellularheatv insulation. material of high compressive strength and rigid lowthermal conductivity sheets secured to the opposite faces of said body;means securing, said sandwiches to said posts and carlines, said meansextending only through the. outer ones of. said rigid sheets, saidcentral bodies and inner rigid sheets being perforated. to render saidsecuring means accessible from inside the car and. lining, and lowthermal conductivity plugs. S cured inthe perforations to complete theinsulating of said shell.

3. The combination with a. refrigerator car having an outer shell havinginternal. posts and carlines, of a. thermal insulation lining, com.-prising: sandwiches of insulation covering the; sides, ends, ceiling andfloor of the. shell andv disposed against the inside faces of said postsand carlines, said sandwiches, each comprising; a pair of rigid sheetsof low. thermal conductivity material with a body of lower thermalconduc-- tivity material of high compressivestrength fix d.therebetween, brackets fixed on said, posts and carlines and abuttedagainst. the. outer. onesof. said rigid sheets, bolts extending throughsaidbrackets and theouter ones; of. said rigid sheets: to secure thesandwiches to the. shelLsa-idinner. rigid sheets and said body ofmaterial containing; perforations through which said-iboltsare.accessible, and plugs. composed of: the. same: materials; as said innerrigidlsheets and-.bodm'of material. for plugging said perforations to,render saidbody of material uninter un v material? or higher thermalconductivity;

4. The combination witha refrigerator: car; which has a floor,. roof andsidezand-zendwalls' mpri n ash ll for, said can or a. thermal insulationlining therefor comprising a hard surfaced sheet having bonded thereto asheet of insulation material of low thermal conductivity, said materialbeing sufficiently rigid to be selfsupporting, and having suificientstrength in compression to withstand the pressure of the car-lading,means for securing said insulation to the inside shell of said car withthe hard surfaced sheet forming the interior wall of the car, said meansextending only partially through the insulation adjoining the shell ofsaid car, the hard surfaced sheet and insulation material beingcounter-bored to render said securing means accessible from inside thecar and lining, and low thermal conductivity plugs for filling andsealing said perforations to provide a smooth and uninterrupted lowthermal conductivity insulationlining. for said car.

5. The combination with a refrigerator car which has a floor, roof andside and end walls comprising a shell therefor, and has interal postsand'carlinesof a thermal insulation lining therefor consisting of aself-supporting substance of low thermal conductivity and highcompressive strength, brackets on said posts and carlines, means forsecuring said insulation to said brackets, said means extending onlypartially through the said insulation, said insulation beingcounterbored to render said securing means accessible from the innerside thereof, and low conductivity seals for filling nd closing thecounterbores to complete the thermal insulation of said car.

6. The combination with a refrigerator car the like which has a floor,roof and side and end walls comprising a shell for said car, of athermal insulation lining therefor composed of insulation sandwichescomprising two hard surfaced sheets having bonded therebetween a centralsheet of insulation material of low thermal conductivity. said materialbeing sufliciently rigid to be selfsupporting and'having sufficientstrength in compression to withstand the pressure of the carlading,means for securing said insulation sandwich to the inside face of theouter shell of said car,.said means extending. only through the outersheet of said sandwich adjoining the said shell, the other of saidoutside sheets and the central sheet of insulation material beingperforated to render. said securing means accessible from inside the carand lining, and low thermal conductivity plugs for filling and sealingsaid perforations to provide a smooth and uninterrupted low thermalconductivity insulation lining for said car.

'7'; The combination with a refrigerator car having an outer shellsupported by internal posts and carlines; of a laden supportinginsulation lining therefor that is entirely free from members havingthermal conductivity higher than that of the insulation, comprising:outer rigid wooden members disposed against said posts and carlines;bolts securing said members to said posts and carlines; slabs of rigidfoamed polystyrene butted together and cemented to said outer members;and inner wooden members butted together and cemented to said styreneand forming the laden engaging inner facing of the; car.

8. The combination with a refrigerator car having a floor and an outershell supported by nternal posts and carlines; of a laden supportmg;insulation lining therefor that is entirely free from members havingthermal conductivity higher than that of the insulation, comprising:outer members of moisture resistant plywood butted together and disposedagainst said posts, carlines and floor; bolts securing said members tosaid posts, carlines and floor; slabs of foamed polystyrene, which isnon-fragile and has high compressive strength, butted together andcemented to said outer members with moistureproof cement; and innermembers composed of moisture resistant plywood butted together andcemented to said polystyrene with moistureproof cement.

PAUL TALMEY.

References Cited in the file of this patent UNITED STATES PATENTS NumberNumber Name Date 2,134,705 Crecca, Nov. 1, 1938 2,174,988 Lundvall Oct.3, 1939 2,239,109 Lundvall Apr. 22, 1941 2,266,746 Elmendorf Dec. 23,1941 2,307,787 Morrell Jan. 12, 1943 7 2,323,936 Roberts July 13, 19432,342,682 Miller Feb. 29, 1944 2,376,653 Boyer May 22, 1945 OTHERREFERENCES Scientific American, September 1945, pages

